Centre National de la Recherche Scientifique, Institut de Pharmacologie et de Biologie Structurale, BP 64182, 205 route de Narbonne, 31077 Toulouse, France.
J Membr Biol. 2012 Sep;245(9):565-71. doi: 10.1007/s00232-012-9468-9. Epub 2012 Jul 15.
Despite great potential for disease treatment, small interfering RNA (siRNA) development has been hampered due to its poor stability and the lack of efficient delivery method. To overcome the sensitivity, new generations of chemically modified oligonucleotides have been developed such as the locked nucleic acid (LNA). LNA substitution in an siRNA sequence (siLNA) is supposed to increase its stability and its affinity for its complementary sequence. The purpose of this study was to evaluate the potential benefit of an anti-GFP siLNA using the biophysical delivery method electropermeabilization. We used two types of electrical conditions: electrochemotherapy (ECT), a condition for efficient transfer of small molecules in clinics, and electrogenotherapy (EGT), a condition for efficient transfer of macromolecules. We first confirmed that siLNA was indeed more stable in mouse serum than unmodified siRNA. After determining the ECT and EGT optimal electrical parameters for a human colorectal carcinoma cell line (HCT-116) expressing eGFP, we showed that modifications of siRNA do not interfere with electrotransfer efficiency. However, despite its higher stability and its high electrotransfer efficacy, siLNA was less efficient for eGFP silencing compared to the electrotransferred, unmodified siRNA regardless of the electrical conditions used. Our study highlighted the care that is needed when designing chemically modified oligonucleotides.
尽管小干扰 RNA（siRNA）具有很大的疾病治疗潜力，但由于其稳定性差和缺乏有效的递送方法，其发展受到了阻碍。为了克服这种不稳定性，人们开发了新一代的化学修饰寡核苷酸，如锁核酸（LNA）。在 siRNA 序列中进行 LNA 取代（siLNA）被认为可以提高其稳定性和与互补序列的亲和力。本研究旨在评估使用物理传递方法电穿孔的抗 GFP siLNA 的潜在益处。我们使用了两种类型的电条件：电化学疗法（ECT），这是一种在临床上有效传递小分子的条件，以及电基因疗法（EGT），这是一种有效传递大分子的条件。我们首先证实 siLNA 在小鼠血清中的稳定性确实高于未修饰的 siRNA。在确定了表达 eGFP 的人结肠直肠癌细胞系（HCT-116）的 ECT 和 EGT 最佳电参数后，我们表明 siRNA 的修饰不干扰电转移效率。然而，尽管 siLNA 具有更高的稳定性和更高的电转移效率，但与电转移的未修饰 siRNA 相比，其 eGFP 沉默效率较低，无论使用何种电条件。我们的研究强调了在设计化学修饰寡核苷酸时需要注意的问题。
